Deforestation
In GCSE Biology, by definition, deforestation refers to the large scale cutting down of trees for timber or agricultural use. Land for agriculture gained from deforestation is used for..
- Growing crops for biofuels based on ethanol
- Organisms like cattle and rice fields to feed a growing population (these organisms releases methane which leads to increased levels of methane in the atmosphere.
Deforestation had happened in many tropical areas with devastating effects on the environment. Local effects of deforestation:
- Causes the displacement of people
- Can destroy homes and culture
- Having no roots in the soil makes it unstable, so it is washed away when it rain. This means that the ground lacks minerals and will eventually become infertile.
Usually in GCSE Biology, global effects of deforestation include:
- Increased the amount of carbon dioxide released into the atmosphere by the burning and decay of chopped down wood by microorganisms
- Decreased the rate at which carbon dioxide is removed from the atmosphere by photosynthesis
- Increase levels on methane in the atmosphere (from organisms like cattle)
- Loss of forests can lead to a reduction in biodiversity, and can result in the loss of organisms that could be of use in the future (e.g, for medicines)
Destruction of peat
In GCSE Biology curriculum, peat bogs are areas of wetland made up of barely decomposed vegetation. Over many years layers of dead vegetation build up in the wet lands, but they aren't decomposed because there isn't enough oxygen in the water for the microorganisms to respire, this is how peat is then formed.
Peat bogs are harvested unsustainably. When peat bogs are drained microorganisms can then decompose the plant material, which releases carbon dioxide into the atmosphere as they respire.
Peat is also used for fuel, this releases carbon dioxide into the atmosphere when it is burnt (the carbon compounds contained within the plant material reacts with oxygen in the air to form carbon dioxide).
The destruction of peat bogs and other areas of peat releases carbon dioxide into the atmosphere.
Peat is used in composts because it has good water holding properties. In GCSE biology, using peat free composts could help to reduce the environmental effects of peat.
End of the topic!
Drafted by Gina (Biology)